An oil or gas well for extracting fluids such as petroleum oil hydrocarbons from a subterranean formation can include one or more subsurface safety valves for restricting fluid flow from the well. A subsurface safety valve can include a selectively actuated closure mechanism, such as (but not limited to) a flapper valve. Selecting an open or closed position of the closure mechanism can prevent or otherwise restrict the flow of fluids from the subterranean formation toward the surface of the well.
The subsurface safety valve can sometimes cease to function. In one example, the subsurface safety valve can experience malfunctions causing the subsurface safety valve to enter a fail-safe configuration. In a fail-safe configuration, the closure mechanism of the subsurface safety valve can be set to a closed position, thereby preventing the flow of fluid from the well. In another example, a subsurface safety valve can require periodic maintenance. The closure mechanism can be set to a closed position while maintenance operations are performed.
When a subsurface safety valve is malfunctioning or otherwise inoperative, an insert valve having a second closure mechanism can be deployed in the wellbore. The insert valve can be positioned within the inner volume of the subsurface safety valve. Positioning the insert valve within the inner volume of the inoperative subsurface safety valve can set the closure mechanism of the subsurface safety valve to an open position. The closure mechanism of the insert valve can be selectively actuated to allow, prevent, or otherwise control the flow of fluid toward the surface of the well. The insert valve can thereby allow for continued production from the well when the subsurface safety valve is inoperative.
Prior solutions involve an inoperative subsurface safety valve and the insert valve using the same actuation mechanism to actuate their respective closure mechanisms. For example, the closure mechanism of an insert valve may be actuated by the same control line that is used to actuate the closure mechanism of the subsurface safety valve. If the control line malfunctions, neither the closure mechanism of the subsurface safety valve nor the closure mechanism of the insert valve can be actuated, thereby preventing the continue production of fluid from the wellbore.
Prior solutions may also involve using battery powered insert valves. Such solutions require pressurization above the insert valve in order to open the insert valve. Such solutions also use a poppet closure mechanism that can cause a large restriction in the flow path, which can be unsuitable for a safety valve applications involving long term production from a well.
It is desirable for an insert valve to include an actuation mechanism for actuating a closure mechanism the insert valve that can operate independently from an actuation mechanism for actuating a closure mechanism of a subsurface safety valve.